A housewarming party is a party traditionally held within approximately 10 days of moving into a new residence. It is an occasion for the hosts to present their new home to their friends, post moving, and for friends to give gifts to furnish the new home. Housewarming parties are generally informal. Usually there are no planned activities besides a possible tour.
Gifts are customarily necessary. They usually consist of something for the new house (such as a potted plant, a vase, or a picture frame) or something to be enjoyed during the party (such as a bottle of whiskey, a bouquet of flowers, or a gift basket of foodstuffs). Bluebirds are often given in some countries as they are believed to bless the new house with happiness and good luck. Today it is also customary to provide bluebird-themed paraphernalia such as china. Pineapples and coconuts are also common housewarming gifts and the pineapple and coconuts has served as a symbol of hospitality and warm welcome through the history of the Americas.
In East Lancashire as in parts of Scotland (particularly Ayrshire and Banffshire) a frog is seen as a giver of good luck. A gift of a frog is often made as a wedding or housewarming gift for good luck and fertility.
In Germany a housewarming gift may often consist of a gift certificate, for example from a furniture shop. Guests also usually bring something to drink or a homemade dish, such as a salad or a pie.
The term "housewarming" is descended literally from the act of warming a new house, in the days before central heating. Each guest would bring firewood, and build fires in all the available fireplaces, offering firewood as a gift. Aside from warming the house, this was also believed to repel evil spirits by creating a protective atmosphere of warmth. Uninhabited houses were considered targets for vagrant spirits, and therefore used to require a certain level of cleansing before a house was safe to be occupied by young children.
A housewarming party is called a pendaison de crémaillère, literally "hanging of the chimney hook". The expression comes from medieval times. When the construction of the house was finished, it was customary to invite all those who participated in its building to eat dinner as a vote of thanks. The food was prepared in a large pot, the temperature of which was controlled by a chimney hook, which could adjust the pot so it sat higher or lower over the fireplace. This hook was the last thing to be installed in the new house, marking the beginning of the thank you meal.
- In India, this ceremony is known as "Gruha Pravesh" (गृह प्रवेश in Devanagari) or "Gruha Pravesham" (Tamil/Telugu) or "Gruha Pravesha" (Kannada) literally meaning "Entering New House" (for the first time). In some places, they allow a cow (sacred animal among the Hindus) to be the first to get inside the house.This is done as the first part of the ceremony. The ceremony usually involves VastuShant (वास्तुशांत in Devanagari).
- In Thailand, the traditional Thai housewarming is a Buddhist ritual where monks, family, friends and food all play an important part. 
- In New Zealand, the United Kingdom and other Commonwealth countries, a housewarming party may also be known as a flatwarming party, usually in a shared living situation involving flatmates.
- A housewarming party may be thrown upon completion of renovation or remodel.
- A housewarming party may be presented as an "open house" where people are free to come and go during a fixed window of time on a given day.
- A housewarming may involve a potluck meal.
- Some people invite all of their new neighbors to their housewarming. This allows the hosts to meet their new community.
- In some communities, neighbors may bring the housewarming party to the new residents to welcome them.
- While people try to host a housewarming party within the first 3 months, a lot of people wait until they are completely settled in. The time frame is flexible, and a party can qualify as a housewarming anytime after the move-in date.
- "Emily Post Institute—Invitation Etiquette". Emily Post.
- "An Etymological Dictionary of Modern English: In Two Volumes – Ernest Weekley – Google Books". Books.google.co.uk. Retrieved 2013-02-18.
- "Thai Housewarming Ceremony – Monks, Family, Friends & Food » Temple of Thai Food". Templeofthai.com. Retrieved 2013-02-18.